The present invention relates to an apparatus and a method for removing amalgam and waste particles from dental office suction effluent.
In dentistry and in the present specification, the term “amalgam” generally refers to the alloys of mercury and other metals such as silver, tin, copper, which are used to form dental restorative materials (e.g., fillings). Amalgam was the restorative material of choice for many years due to its relatively low cost, ease of application, strength and durability. However, it has become less popular due to concerns over the toxicity of mercury, which is the major component of amalgam, the development of alternative materials that are more aesthetically pleasing, and also due to concerns over environmental pollution.
Although amalgam is less frequently used for new dental fillings than was the case some decades ago, amalgam nevertheless continues to comprise a significant portion of the metallic particle component of dental office effluent. This is the case because when old fillings comprising amalgam are drilled out and removed, amalgam particles are evacuated from the mouth as waste in such effluent. Furthermore, amalgam continues to be preferred for some tooth filling applications.
In addition to amalgam, dental office suction effluent includes saliva, rinsing fluid and solid particles such as aluminum oxides, which are used in abrasion treatments. It is important that the solid components of dental office suction effluent be separated from the liquid wastes before the latter are discharged into sanitary treatment systems.
The International Organization for Standardization (hereinafter “ISO”) has adopted a standard, which specifies the efficiency of amalgam separators in terms of the level of retention of amalgam based on a laboratory test (ISO 11143:2008). And there are many amalgam separators available that comply with such standard.
One amalgam separator known in the art is sold by SolmeteX, Inc. of Northborough, Mass. under the trade designation HG5®. This device consists of an upper chamber having two openings in an upper end and two openings in a lower end. One of the openings in the upper end is in fluid communication with a vacuum pump via piping, and the other opening in the upper end is in fluid communication with a dental suction wand. A collection chamber is removably connected to the lower end of the upper chamber. Waste is drawn into the upper chamber through the dental suction wand with air drawn into the upper chamber by the vacuum pump. Liquids and solids in the dental suction effluent stream are separated from the air to some degree in the upper chamber. The air flows out of the upper chamber to the vacuum pump. The liquids and solids flow under the force of gravity through one of the openings in the lower end of the upper chamber and then through straight tubing into the collection chamber. Solid particles settle and accumulate in the bottom of the collection chamber. Liquid waste is drawn up through a filter that extends into the collection chamber from the second opening in the lower end of the upper chamber. This opening is in fluid communication with a bypass conduit, which is connected to the piping to the vacuum pump. While the SolmeteX HG5® amalgam separator, and other similar products, are capable of separating amalgam and other solid particles from dental waste effluent streams, there is substantial room for improvement in terms of collection capacity, separation efficiency and ease of use.